Regulating system



Aug. 6, 1929. E. 1.. HOUGH 1,723,039

REGULATING SYSTEM Filed April 19, 1927 Inventor: Eugene L. Hough,

Patented Aug. 6, 1929.

UNITED. STATES PATENT OFFICE.

"EUGENE L. 'HOUGH,OF"ST.. LOUIS, MISSOURI, "ASSIGNQR TO GENERAL'EIIECT'RIC COM- PANY, A CORPORATION OF NEW YORK.

BEGULATING SYSTEM.

2 Application filed April-19,1927. Serial No. 185,035.

My invention relates to regulating systems for maintaining a predetermined division of-load-between a plurality of parallel machines and its. object is to provide. an improved system for accomplishing this result.

My invention isv especiallyapplicable to a. regulating system for maintaining the load properly divided; between a plurality of- -overcompound direct current generators connected to a common load.

My-invention willbe better understood from the following description taken in connection with the accompanying drawing, vwhich shows in invention in connection 'with a'load regu ating system for two overcompound direct current generators connected .inparal'lehand its scope will be pointed out in the appended claims.

Y Referring to the; accompanying drawing, 1 and 2 are two overcompound direct current generators which are respectively, con nected to the :direct current load circuit 3 by suitableswitchingmeans 4 and 5. These switching means may be of any suitable type and may be controlled either manually or automatically. -For example, eachmeans may form a. partzof an automatic switching equipment, examples of which are well kIlOWIldlLl hQ' art, whereby it is closed automatically after the respective generator has been startedtand has reached a predetermined condition.

Each generator is provided with the usual series,..connnutating,- and shunt field windings. As; showmin the drawings, 7 and 8 are the series field windings, 9 and 10- are the connnutatingfield windings, and ll and 12arethe shunt field windings of. the generators 1 and 2 respectively.

The series windings 7 and Sure arranged to: be connected in parallel byJ-the equalizer 13.v A suitable switchingdevice is associated witheach generator for connecting the series winding to the equalizer. In the system shown in the: drawing I provide, the control switches 14 and.15,associa-ted with v the generators 1 and 9 respectively, for this purpose. It will be observed" that when both of the switches Hand 15 areiclosed the series windings Tand Sare in parallel and if their resistances are equal,..-which-is the preferable arrangement, the current flow ngthrough eachseries field is the averageot the currents supplied-by both generators. If, however, the resistances of the windings?- and 8-are unequal the total load current divides-between them inversely as their respectiveresistances. In both-cases the voltage dropacross the parellel con nected series windings isequalto the product of the total load current and the resultant resistance 'otlthe parellelconnected windings.

For regulating the excitationsof the two generators-sothat the load is-divided equally between them, I provide suitableqciu rcut limiting means 15=and 16, shown as resistors,,in the circuits ofthe shunt field windings-'11 and 12 respectively, and diiierential relays 17: and 18 of any suitable type, examples of which are-well known in the art, for respectively controlling a short circuit around the resistors 1-5 and 16 in. accordance with apredeter'minerl relation between the total current supplied by both of the generators and the current supplied by each generator, Asshown' the difi erenti al relay 17 comprises an armature; 19= pivotally mounted between two windings 20 and 21 which are wound differentially with respect to each other and which are respectively connected so as to be energized in accordance with the tOllflluCtlllBIlt output of the two generators and the current out-put of the generator 1. As shownthe winding 2O is connected iirparallel with the series winding 7 and the winding 21 is connected in parellel with the commutating winding 9. The armature 19 also is pivoted; between polar projections of a stationary-:mag-nctic .member 22 which preferably magnetized by a suitable magnetizing winding 23. As shown .the magnetizing winding 23 energized from the circuit 3 butit isobvious that it may be supplied with current from any other suitable-source. The armature 19, therefore, occupies (li ti'erent. positionsdepending upon the direction I and magnitude of the resultant.inilgnetomotive force produced by the currents throughthe windings 20 and 21. The armature'19 is normally biaseclto the position: shown'in thedrawing so that when the ampere-turnsrof the windshunt field windings 11 ings and 21 are equal or the ampere turns .of the Winding 21 exceed the ampere turns of the winding 20 the contacts 24 of the relay 1? are open.v When, however, the ampere turns 01 the winding 20 exceed the ampere turns of the winding 21, the relay closes its contacts 24,'thereby short-circuiting a control relay 25 which is connected across the circuit 3 with a suitable resistor 26 in series therewith. The relay 25 when deenergized closes, through its contacts 27 a short circuit around the resistor 15 in the circuit of the shunt field winding 11.

The rela 18 is similar in construction to therelay 1 It is provided with an armature 28 pivotally mounted between two windings 29 and 30 respectively connected in parallel with the series field winding 8 and the series commutating winding 10 and between the polar projections of a stationary member 31 which is magnetized by a magnetizing winding 32 connected across the circuit 3.

The relay 18is arranged to close its contacts 33 and short-circuit a relay 34 when the ampere turns of the winding 30 are less than the ampere turns of the winding 29. The relay 34 is connected in series with a resistor 35 across the circuit 3 and by closing its contacts 37 when deenergized, completes a short circuit around the resistor 16 in the circuit of the shunt field winding 16-.

Suitable adjustable rheostats 39 and 40 may alsobe provided in the circuits of the and 12 respectively for manually controlling the excitations of the generators.

The operation of the regulating system shown in the'drawing is as follows: When the generators are supplying current to the load circuit 3 and their'associated equalizer switches are closed, the associated regulating relays operate to maintain the proper load on the generators. Let it be assumed that both generators are supplying current and that both of the equalizer switches 14 and 15 are closed. If the generator l'tends to take less than its share of the load the winding 21 of relayl? is energized so that the ampere turns thereof are less than the ampere turns of the winding 20 which is energized in accordance with the total current of the two generators. Consequently,-relay 17 closes its contacts 24 and short-circuits relay 25 which in turn completes a short circuit around the resistor 15 so that the excitation of the generator 1 is increased to cause it to increase its current output.

Similarly, if the generator 2 tends to take less than its share of the load the energization of winding 30 is such that its am ere turns are less than the ampere turns 0 the winding 29. .Therefore, relay 18 closes its contacts 33 and deenergizes relay 34 which in turn short circuits the resistor 16 in the mutating field winding and circuit of the shunt field winding 12 so that the excitation of the generator 1 is increased to cause it to increase its portion of the total load. I

While I have in accordance with the patent statutes shown and described my invention as applied to a particular system and as embodying various devices diagrammatically indicated, changes and modifications will be obvious to those skilled in the art, and I, therefore, aim in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of my invention. Y

What I claim as new and desire to secure by Letters Patent of the United States, is

1. In a regulating system, two generators connected in parallel, means associated with each generator and connected in series therewith, an equalizer for connecting said means in parallel, and a relay for controlling the excitation of one of said generators comprising two differential windings respectively energized in response to the current flowing through said one of said generators and the voltage drop across said parallel connected means.

2. In a regulating system, two overcompound direct current generators connected in parallel, an equalizer for connecting certain of the series field windings of said generators in parallel, and a relay associated with each generator for controlling the excitation thereof comprising two differential windings respectively energized in accordance with the current flowing through the generator and the total current flowing through said parallel-connected series field windings.

3. In a regulating system, a plurality of overcompound direct current generators connected in parallel, each generator having a series field winding and a connnutating field winding, switching means associated with each generator for connecting its respective series field winding in parallel with the series field windings of the other generators, and a differential relay associated with each generator for controlling the excitation thereof comprising a winding con nected in parallel with itsrespective coman opposing winding connected in parallel with its respective series field winding.

4. In a regulating system, two sources of 'current connected in parallel, means associated with each source and connected in series therewith, an equalizer for connecting said means in parallel, and av relay for controlling the output of one of said sources comprising two cooperating windings respectively energized in response to the current supplied by one of said sources and the voltage drop across said parallel series conneeted means. I i

5. In a regulating system, two generators connected in parallel, each generator having a series field winding, an e ualizer for connecting said series field win ings in parallel,

- and a relay for controlling the excitation of one of said generators comprising two 00- operatrng WlIldlIlgS respectively energized in response to the currents flowing through one of said generators and the voltage drop across said parallel connected series field 1 windings.

In witness whereof, I have hereunto set my hand this 16th day of April, 1927.

EUGENE L. HOUGH. 

